CVE-2026-68419
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk3th percentile - higher than 3% of all known CVEs
Summary
In the Linux kernel, a vulnerability in the RDMA/irdma driver allows a user to invoke rereg_mr on special memory regions (used for QP/CQ/SRQ creation) that lack a valid mkey. This triggers a real CQP command with a zero mkey, potentially causing incorrect behavior.
Risk Assessment
The risk includes potential disruption of the RDMA driver, which may lead to system instability or incorrect I/O operations.
Recommendation
It is recommended to update the Linux kernel to a version containing the fix that prevents rereg_mr on these special memory regions.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: RDMA/irdma: Prevent rereg_mr for non-mem regions When a QP/CQ/SRQ is created, a two step process is used where the buffer is allocated in userspace and explicitly registered with the normal reg_mr mechanism prior to creating the actual QP/CQ/SRQ object. These special registrations are indicated via an ABI field so the driver knows that they do not have a valid mkey and to skip the actual CQP command submission. Since these are real MR objects from the core's perspective, it is possible for a user application to invoke rereg_mr on them and cause a real CQP op to be emitted with the zero-initialized mkey value of 0. Fix this by preventing rereg_mr on these special regions.